Small trailer tire inflation system

ABSTRACT

A tire inflation system for a small trailer may include a fluid pressure source mountable to the trailer, and fluid conduits providing sealed fluid communication between the fluid pressure source and the small trailer&#39;s pneumatic tires. The system may further include a fluid connector configured for connection to an external fluid power source.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a division of U.S. patent application Ser. No.14/258,804 entitled “SMALL TRAILER TIRE INFLATION SYSTEM” filed Apr. 22,2014, which issued as U.S. Pat. No. 9,789,739 on Oct. 17, 2017, whichclaims benefit of U.S. Provisional Patent Application Ser. No.61/815,003 entitled “SMALL TRAILER TIRE INFLATION SYSTEM” filed Apr. 23,2013, the entire disclosures of which are herein incorporated byreference.

FIELD

This field generally relates to tire inflation systems for smalltrailers.

BACKGROUND

Many small trailers, such as light- and medium-duty trailers, have twoor more pneumatic tires requiring inflation as specified by the tiremanufacturer. Such trailers may have a variety of uses, may be usedinfrequently, and often have improperly inflated tires. There remains aneed for a tire inflation system for such trailers.

SUMMARY

A tire inflation system for a small trailer comprising an axle and apneumatic tire mounted at each end of the axle, the system comprising afirst rotary fluid connection mounted at a first end of the trailer axleand in sealed fluid communication with a first pneumatic tire mounted atthe first end of the trailer axle; a second rotary fluid connectionmounted at a second end of the trailer axle and in sealed fluidcommunication with a second pneumatic tire mounted at the second end ofthe trailer axle; a fluid connector configured for sealed connection toan fluid pressure source external to the small trailer, the first rotaryfluid connection and the second rotary fluid connection being in sealedfluid communication with the fluid connector such that fluid flowinginto the fluid connector from the stationary fluid pressure source mayflow substantially simultaneously into the first and second pneumatictires; a first one-way valve disposed between and in sealed fluidcommunication with the fluid connector and the first pneumatic tire, thefirst one-way valve disposed so as to allow fluid to flow to the firstpneumatic tire and not from the first pneumatic tire to the fluidconnector or to the second pneumatic tire; a second one-way valvedisposed between and in sealed fluid communication with the fluidconnector and the second pneumatic tire, the second one-way valvedisposed so as to allow fluid to flow to the second pneumatic tire andnot from the second pneumatic tire to the fluid connector or to thefirst pneumatic tire.

A tire inflation system for a small trailer comprising an axle and apneumatic tire mounted at each end of the axle, the system comprising afluid pressure source mounted to the small trailer, the fluid pressuresource powerable by energy provided by a small-trailer tow vehicle; afluid conduit providing sealed fluid communication between the fluidpressure source and each pneumatic tire so as to allow pressurized fluidfrom the trailer-mounted fluid pressure source to flow from the fluidpressure source to each pneumatic tire; and a fluid connector providingsealed fluid communication with the pneumatic tires, the fluid connectorcomprising a one-way valve configured for sealed fluid communicationwith an external fluid pressure source so as to allow fluid to flow fromthe external fluid pressure source to each pneumatic tire.

A method of inflating small trailer pneumatic tires, the small trailercomprising an axle and a pneumatic tire mounted at each end of the axle,the method comprising providing a fluid connector comprising a one-wayvalve configured for sealed fluid communication with an external fluidpressure source not mounted to the small trailer or to a tow vehicle;providing sealed fluid communication between the fluid connector andeach pneumatic tire; and connecting the fluid connector to the externalfluid pressure source so as to allow pressurized fluid to flow from thefluid pressure source to each pneumatic tire substantiallysimultaneously.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A illustrates a side view of an embodiment of a trailer inflationsystem having a fluid source mounted to the trailer.

FIG. 1B illustrates a bottom view of an embodiment of a trailerinflation system having a fluid source mounted to the trailer.

FIG. 2A illustrates a side view of an embodiment of a trailer inflationsystem having a fluid source mounted to the tow vehicle.

FIG. 2B illustrates a top view of an embodiment of a trailer inflationsystem having a fluid source mounted to the tow vehicle.

FIG. 3A illustrates a side view of an embodiment of a trailer inflationsystem including a control box.

FIG. 3B illustrates a bottom view of an embodiment of a trailerinflation system including a control box.

FIG. 4 illustrates an embodiment of a trailer inflation system includingcheck valves.

FIG. 5 illustrates an embodiment of a trailer inflation system includinga pressure regulator and check valves.

FIG. 6 illustrates an embodiment of a trailer inflation system includinga pressure relief valve.

DETAILED DESCRIPTION

As may be seen in the embodiment of FIG. 1, a trailer 100 may includeone or more axles 112. As may be seen in the top and side views oftrailer 100, each axle 112 may have one or more wheels 102 rotatablymounted thereto. A wheel assembly at the end of an axle may include avariety of wheel configurations, e.g., single-wheel configuration or adual-wheel configuration. A pneumatic tire 104 may be mounted to eachwheel 102. Each axle 112 may have one tire 104 at each end of the axle112, or may have two or more tires 104 attached at each end of the axle112. A hub cap 114 or grease cap may be mounted to each wheel 102 tosubstantially seal the wheel bearings (not shown) from contamination.

The trailer 100 may be any trailer of the sort capable of being pulledby a non-class 8 vehicle. Such trailers may include, for example, boattrailers, horse trailers, flatbed trailers, vehicle tow trailers, cargotrailers, livestock trailers, jet ski trailers, travel trailers, pop-upcamper trailers, RV trailers, and utility trailers. Such trailers may beattached to any suitable vehicles, such as a pickup truck, a passengercar, van, SUV, ATV, motorcycle or other vehicle. Such trailers may beattachable to such vehicle by a bumper-mounted hitch ball, clevis hitch,or fifth-wheel or goose-neck hitch configuration, or any other suitableattachment mechanism. Such trailers may include no brakes, or mayinclude electrically-operated brakes powered by a tow vehicle, or mayinclude hydraulic or surge brakes. The disclosed method and apparatusmay generally be used for trailers without air brakes.

The trailer 100 may be provided with a tire inflation system (TIS) thatuses pressurized air to maintain the tires 104 at or fill the tires 104to a desired air pressure. The TIS may comprise an on-board aircompressor 106 mounted to the trailer 100 at any suitable location. Theair compressor 106 may be any suitable air compressor, such as acompressor driven by electric motor or combustion engine. If, forexample, the compressor 106 is electrically driven, the compressor maybe powered by a battery or generator mounted to the trailer 100, or maybe powered by the vehicle to which the trailer 100 is attached. Anelectric compressor may, for example, run from a 12V or 24V vehicleelectrical system, and may be connected to a tow vehicle by electricalconnection 107. Electric air compressors may be of any suitable make andmodel, such as Hadley 850 Series Mini Compressor, Oasis XD 3000 ExtremeDuty Air Compressor, Viair 495C Air Compressor, Chassis Tech DC7000 AirCompressor, Air Zenith OB2-200 Air Compressor, Pacbrake HP625 Series AirCompressor, and Helix UltraAer Air Compressor.

Of course, other pressure sources may be used, as well, either as analternative to an air compressor, or in addition to an air compressor.In an embodiment, a trailer-mounted air pressure source may comprise apressurized air tank or high-pressure compressed gas cylinder. The airtank or gas cylinder may be filled with any suitable tire pressurizingfluid, such as air, nitrogen-enriched air or pure nitrogen. In someembodiments, an air compressor may be provided on a tow vehicle 105. Forexample, a tow vehicle may have an air compressor driven by the vehicleengine, such as an air compressor mounted to the vehicle engine anddriven by a belt. In other embodiments, an electric- or engine-poweredair compressor 106 may be mounted at a different location on the vehicle105, such as seen in the embodiment of FIG. 2. An electric compressor106 mounted to the vehicle 105 may be powered by a 12V or 24V vehicleelectrical system. In yet further embodiments, an engine-poweredcompressor may be mounted to, for example, the bed of a pickup truck. Anair compressor may be used with or without an air tank to holdpressurized air.

The TIS may further comprise one or more air conduits 108 that mayprovide pressurized air to the tires 104. The air conduits 108 maycomprise a variety of paths and configurations. In some embodiments, theair compressor may comprise a tank to hold pressurized air at a pressuresuitable for delivery without pressure reduction to the tires. In otherembodiments, such a tank may hold pressurized air at an air pressurethat is too high for the trailer tire. An air conduit 108 may permitcommunication of pressurized air from the air compressor to a pressureregulator 110 that may reduce the air pressure to a pressure suitablefor a trailer tire, such as, for example, 35 psi. A regulator may be ofany suitable type, such as model LR-1/8-D-0-mini-NPT manufactured byFesto, and may be set to pass air through at any pressure suitable formaintaining a desired tire inflation pressure. An air filter may beprovided to clean the air passing to the regulator, and a shut-off valvemay be provided to selectively permit or prevent fluid communicationbetween the air compressor and the regulator.

In yet further embodiments, a source of pressurized air may be externalto the trailer 100 and tow vehicle 105. Such a source may be, forexample, a compressed-air tank or air compressor placed at a vehiclemaintenance facility or service station, or on a service vehicle. Forsuch an embodiment, a control box 109 may be provided as illustrated inFIG. 3 to house an air connection (not shown) for connecting the TIS tothe external pressure source. The control box 109 may house one or moretypes of air connection, such as a tire valve, a quick-connectsleeve-type pneumatic coupling, and the like, and may serve to protectthe air connection from damage and contamination. In yet furtherembodiments, a control box 109 may not be required, and conduit 108 maysimply be provided with an air connection to allow sealing connectionwith the external air pressure source. In such an embodiment, alltrailer tires may be inflated in a substantially simultaneous manner.Thus, for example, a trailer that has been stationary all night may haveits tires quickly and simultaneously inflated before use by connectingthe TIS to a garage or shop air pressure source. Similarly, providing asmall trailer TIS may make it easier to inflate trailer tires at a truckstop, by avoiding the need for moving an external air source hose fromtire to tire.

In yet other embodiments, a pressure relief valve (“PRV”) may beprovided in sealing fluid communication with the conduit 108. The PRVmay be set to open when the TIS system pressure exceeds the pressuredesired for the tires. Thus, if higher-pressure shop air is used toinflate the tires, a PRV may be used to prevent over-inflation.

In some embodiments, the pressurized air communicated from the aircompressor may pass through the trailer axles. Some trailers may includehollow axles 112 that may be sealed at each end by a cap or plug, suchas those described in one of U.S. Pat. Nos. 5,584,949, 5,769,979,6,131,631, 6,394,556, 6,892,778, and 6,938,658, or by any other suitablethreadable cap or insertable axle plug. The plug or cap, in someembodiments, may serve more to support air conduits or rotary airconnections (or components thereof) than to seal the hollow axle to holdpressurized air, such as a plug or cap disclosed in one of U.S. Pat.Nos. 6,325,124 and 7,273,082. An air conduit may be sealingly connectedbetween the air compressor and the axle, thus allowing communication ofair from the air compressor to the sealed axles. Thus sealed, each axlemay serve as part of the air conduit to communicate pressurized air tothe tires. In other embodiments, an air conduit may be provided from theair compressor through the hollow axles without need for sealing theaxles.

In yet other embodiments, the trailer axles may be solid. In suchembodiments, an axial hole may be drilled in the axles, and the axlesmay be further sealed with a stator or with a plug as described above.Alternatively, an air conduit may be provided through the hole drilledin the solid axle without need for sealing the axle.

The TIS may further comprise a rotary air connection mounted on or inthe wheel-end assembly to allow communication from air compressor to therotatable tires so as to allow pressurization of the tires. Suitablerotary unions, and other suitable TIS components, may include thosedisclosed, for example, in U.S. Pat. Nos. 5,377,736, 6,698,482,6,105,645, 6,325,124, 6,325,123, 7,302,979, 6,269,691, 5,769,979,6,668,888, 7,185,688, 7,273,082, 6,145,559, 6,425,427, 7,963,159, andU.S. Pat. Pub. No 2009/0266460, the disclosures of which areincorporated herein by reference. Thus, any suitable rotary coupling maybe used to communicate air between the air compressor and the rotatabletires. For example, with respect to U.S. Pat. No. 5,769,979, a statormay be mounted in a hollow or axially-drilled axle. In some embodiments,a stator (not shown) may be mounted in a cap or plug sealing an axle,such as the one described above, or affixed to the end of an air conduitprovided through a hollow or axially-drilled axle. A rotary connection114 may be mounted to the rotating wheel, such as on a hub or grease cap(not shown), and air hoses 116 may be sealingly provided between therotary connection and the tires.

Thus, in some embodiments, one or more trailer axles may be hollowsealed axles. The axles may be hollow and may be sealed to serve as partof a conduit for pressurized air. An air conduit may be sealinglyconnected to the axle to allow pressurized air to flow from the aircompressor or pressure regulator to the axle. The pressurized air mayflow through the axle to a rotary air connection mounted in or near theaxle end as described in more detail below. An air hose may connect tothe rotary air connection to a valve stem of a wheel to which thepneumatic tire is mounted, thus allowing pressurized air to flow toand/or from the tire. In some embodiments, the air conduit may besealingly connected to a tee 120 to allow pressurized air to flow to asecond axle.

An air conduit may, in other embodiments, be disposed in the traileraxle. The axle may carry an air conduit to communicate pressurized airto a rotary air connection, for example, such as is disclosed in U.S.Pat. Nos. 6,325,124 and 7,273,082. Air hoses may connect the rotary airconnection to the valve stem of the wheel to which the pneumatic tire ismounted, thus allowing pressurized air to flow to and/or from the tire.In other embodiments, if the axle is solid, then a channel may be boredin the axle to permit positioning of all or part of conduit inside theaxle.

Of course, any suitable rotary connection may be provided. In otherembodiments, air conduits may be routed for external attachment to arotary union mounted to the trailer wheels. In such embodiments, airconduits may be routed from the air compressor through brackets mountedto the trailer, such as to the trailer tire fenders. The air conduitsmay be sealingly connected to rotary air connections mounted to thetrailer wheels.

In some embodiments, as may be seen in the embodiment of FIG. 4, aone-way fluid valve 402 may be used for each tire 400 in fluidcommunication with a TIS fluid source 408. A one-way valve 402 may bedisposed in an air conduit 404 unique to a tire 400, and may permitpressurizing fluid to flow toward or into a tire 400, but not out awayfrom or out of a tire. In some embodiments, a one-way valve may be usedin connection with each tire. Thus, if one tire deflates, such as bypuncture, the one-way valves may prevent pressurizing fluid from flowingfrom one or more inflated tires to the deflated tire. A one-way valvemay be disposed, for example, in a rotary union, or in an air conduitbetween a rotary union and a tire, or in an air conduit between a rotaryunion and a pressure source.

In some embodiments, as also may be seen in FIG. 4, a TIS having atrailer-mounted or vehicle-mounted fluid pressure source 408 may alsoinclude a fluid connection 406 connectable to an external fluid pressuresource (not shown). The fluid connection may simply allow for sealedfluid communication between an external fluid pressure source and thepneumatic tires. In other embodiments, the fluid connection may comprisea one-way valve. In such case, it may be desireable to avoid releasingpressurized fluid from the TIS through the fluid connection. Thus, aone-way valve may be used between the trailer- or vehicle-mounted fluidpressure source and the fluid connection to allow fluid to flow from thefluid connection to the TIS, but not from the TIS through the fluidconnection. In one of a variety of embodiments, a trailer-mounted orvehicle-mounted fluid pressure source 408 may be omitted from thesystem, leaving only use of a fluid connection 406 connectable to anexternal fluid pressure source. In such embodiments, a fluid connectionmay prevent pressurized air from the TIS from escaping to theatmosphere. In other variations, a trailer-mounted or vehicle-mountedfluid pressure source 408 may be included from the system, whileomitting a fluid connection 406 connectable to an external fluidpressure source.

As may be seen in the embodiment of FIG. 5, a pressure regulator 410 maybe used to reduce pressure from a pressure source 408 to a pressuresuitable for a pneumatic tire. As may be seen in the embodiment of FIG.6, a pressure relief valve (PRV) 412 may be used in sealed fluidcommunication 414 with the pneumatic tires 400 to preventover-pressurization of the tires by fluid from an external fluidpressure source through a fluid connection 406. The PRV may be set torelease fluid when the pressure in the system reaches a threshold. Thethreshold may, for example, be set at a pressure suitable forpressurizing small trailer pneumatic tires. Of course, the foregoingregulator, PRV, fluid connector and valves may be used in anycombination.

In some embodiments, a high-temperature warning system, such as theThermAlert™ system by PSI disclosed in U.S. Pat. Nos. 6,892,778 and7,416,005, the disclosures of which are incorporated herein byreference, may be used in conjunction with a tire inflation system. Sucha high-temperature warning system may use pressurized air provided viathe regulator. In such embodiments, a flow switch 416 (with reference toFIG. 5) may be fluidly connected to an outlet port of a regulator (suchas regulator 410) or otherwise connected in fluid communication with theair conduit. The flow switch may be connected to a shut-off valve (notshown), which may be connected to a temperature-actuated pressurebarrier, such as a plug with a eutectic alloy that will melt whenreaching a temperature dangerous to continued safe operation of thewheel end. A flow switch may be electrically-coupled to an indicatorlight that may illuminate when fluid flow through the flow switchexceeds a threshold flow. Air may thus flow from the regulator or aircompressor through the flow switch and shut-off valve to the pressurebarrier. If the pressure barrier senses high temperature, it may releasepressurized air, thus activating the flow switch. When activated, theflow switch may send a signal to illuminate an indicator lightpositioned on the trailer within the driver's view. The flow switch maybe powered by the power source provided to power an air compressor or bya battery or other power source, such as a solar panel.

In yet further embodiments, a flow switch may be provided without needfor a high-temperature warning system. In such embodiments, a flowswitch may activate when a tire is rapidly losing air. The flow switchmay send a signal to illuminate an indicator light positioned on thetrailer within the driver's view. The flow switch may be powered by thepower source provided to power an air compressor or by a battery orother power source, such as a solar panel.

In some embodiments, the signal from the flow switch may be transmittedvia wire or wirelessly to an indicator panel in the vehicle cab, orwirelessly to a mobile device. The indicator panel or terminal mayprovide visual or audible indicators of low tire pressure, and mayfurther indicate whether the high-temperature warning system hasdetected a high temperature at a wheel-end assembly. Wirelesstransmission may be by any suitable technology, such as by satellite,Bluetooth, cellular network, WiFi, WiMax, etc.

In some embodiments, the disclosed TIS may be used in connection withtire pressure monitoring systems, such as the wireless tire pressuremonitoring system offered by Pressure Pro. For example, a tire pressuresensor (not shown) may be located at a wheel end. The tire pressuresensor may detect tire pressure and send a signal indicating tirepressure to the driver or remote mobile device.

Of course, references to “air” with respect to tire inflation should beunderstood to include any gas or fluid suitable for inflating a tire,such as pure nitrogen or nitrogen-enriched air.

Although the disclosed embodiments and their advantages have beendescribed in detail, it should be understood that various changes,substitutions and alterations can be made herein without departing fromthe subject matter defined by the appended claims. Moreover, the scopeof the present disclosure is not intended to be limited to theparticular embodiments of the process, machine, manufacture,composition, or matter, means, methods and steps described in thespecification. As one will readily appreciate from the disclosure,processes, machines, manufacture, compositions of matter, means,methods, or steps, presently existing or later to be developed thatperform substantially the same function or achieve substantially thesame result as the corresponding embodiments described herein may beutilized. Accordingly, the appended claims are intended to includewithin their scope such processes, machines, manufacture, compositionsof matter, means, methods or steps.

What is claimed is:
 1. A tire inflation system for a trailer capable ofbeing pulled by a non-class 8 vehicle, the trailer comprising an axleand a first pneumatic tire mounted at a first end of the axle and asecond pneumatic tire mounted to the other a second end of the axle, butwithout air brakes, the system comprising: a first rotary fluidconnection mounted at the first end of the trailer axle and in sealedfluid communication with the first pneumatic tire; a second rotary fluidconnection mounted at the second end of the trailer axle and in sealedfluid communication with the second pneumatic tire; a first fluidconnector configured for sealed connection to a fluid pressure sourcemounted to the vehicle and not to the trailer, the first rotary fluidconnection and the second rotary fluid connection being in sealed fluidcommunication with the first fluid connector such that fluid flowinginto the first fluid connector from the fluid pressure source may flowsubstantially simultaneously into the first and second pneumatic tires;a first one-way valve in sealed fluid communication with the first fluidconnector and the first pneumatic tire, the first one-way valve disposedso as to allow pressurized fluid to flow from the first fluid connectorto the first pneumatic tire but not from the first pneumatic tire toatmosphere when the fluid connector is not in sealed connection to thefluid pressure source; and the first one-way valve further being insealed fluid communication with the second pneumatic tire, the firstone-way valve disposed so as to allow pressurized fluid to flow from thefirst fluid connector to the second pneumatic tire but not from thesecond pneumatic tire to atmosphere when the fluid connector is not insealed connection to the fluid pressure source.
 2. The system of claim 1further comprising a pressure-relief valve (PRV) in sealed communicationwith the first one-way valve and the first fluid connector, wherein thePRV is configured to release fluid when the fluid pressure at the firstone-way valve reaches an excess tire pressure threshold.
 3. The systemof claim 1, further comprising a pressure regulator in sealedcommunication with the first one-way valve and the first fluidconnector, wherein the regulator is configured to reduce fluid pressurefrom the fluid pressure source to a pressure suitable for the first andsecond pneumatic tires.
 4. A tire inflation system for a trailer capableof being pulled by a non-class 8 vehicle, the trailer comprising an axleand a first pneumatic tire mounted at a first end of the axle and asecond pneumatic tire mounted at a second end of the axle, the trailernot being equipped with air brakes, the system comprising: a fluidpressure source mounted to the vehicle, the fluid pressure sourcepowerable by energy provided by the vehicle; a fluid conduit providingsealed fluid communication between the fluid pressure source and each ofthe first and second pneumatic tires so as to allow pressurized fluidfrom the vehicle-mounted fluid pressure source to flow from the fluidpressure source to each of the first and second pneumatic tires; and afluid connector providing sealed fluid communication with the first andsecond pneumatic tires, the fluid connector comprising a first one-wayvalve configured for sealed fluid communication with an external fluidpressure source external to the trailer and vehicle so as to allow fluidto flow from the external fluid pressure source simultaneously to eachof the first and second pneumatic tires separately from the fluidpressure source, the first one-way valve disposed so as to preventpressurized fluid from escaping from the fluid connector to atmospherewhen the fluid connector is not connected to the external fluid pressuresource.
 5. The system of claim 4 further comprising a pressure-reliefvalve (PRV) in sealed communication with the pneumatic tires, whereinthe PRV is configured to release fluid when the fluid pressure in eitheror both of the first and second pneumatic tires reaches a pressurethreshold.
 6. The system of claim 4 further comprising a pressureregulator in sealed communication with the fluid pressure source,wherein the regulator is configured to reduce fluid pressure from thefluid pressure source and from the external fluid pressure source to apressure suitable for the pneumatic tires.
 7. The system of claim 4further comprising: a second one-way valve disposed between and insealed fluid communication with the fluid pressure source and the firstpneumatic tire, the second one-way valve disposed so as to allow fluidto flow to the first pneumatic tire and not from the first pneumatictire to the second pneumatic tire; and a third one-way valve disposedbetween and in sealed fluid communication with the fluid pressure sourceand the second pneumatic tire mount, the third one-way valve disposed soas to allow fluid to flow to the second pneumatic tire and not from thesecond pneumatic tire to the first pneumatic tire.
 8. The system ofclaim 4, wherein the external fluid pressure source comprises compressedair from one of a maintenance facility, service station or mobileservice vehicle.
 9. A method of inflating trailer pneumatic tires, thetrailer capable of being pulled by a non-class 8 vehicle, the trailercomprising an axle and a pneumatic tire mounted at each end of the axle,but without air brakes, the method comprising: mounting to the trailer afirst fluid connector comprising a first one-way valve configured forsealed fluid communication with a fluid pressure source mounted to thevehicle, the first one-way valve disposed so as to prevent pressurizedfluid from escaping from the first fluid connector to atmosphere whenthe first fluid connector is not connected to the fluid pressure source;providing sealed fluid communication between the first fluid connectorand each pneumatic tire; and connecting the first fluid connector to thefluid pressure source so as to allow pressurized fluid to flow from thefluid pressure source to each pneumatic tire substantiallysimultaneously.
 10. The method of claim 9 further comprising: mountingto the trailer a second fluid connector comprising a second one-wayvalve configured for sealed fluid communication with an external fluidpressure source not mounted to the trailer or to the vehicle, the secondone-way valve disposed so as to prevent pressurized fluid from escapingfrom the second fluid connector to atmosphere when the second fluidconnector is not connected to the external fluid pressure source;providing sealed fluid communication between the second fluid connectorand each pneumatic tire; and connecting the second fluid connector tothe external fluid pressure source so as to allow pressurized fluid toflow from the fluid pressure source to each pneumatic tire substantiallysimultaneously.
 11. The method of claim 10 further comprising connectingthe second fluid connector to the external fluid pressure source whenthe fluid pressure source is not providing pressurized fluid, or afterdisconnecting the first fluid connector from the fluid pressure source.12. The system of claim 1, the first fluid connector comprising thefirst one-way valve.
 13. A tire inflation system for a trailer capableof being pulled by a non-class 8 vehicle, the trailer comprising an axleand a first pneumatic tire mounted at a first end of the axle and asecond pneumatic tire mounted at a second end of the axle, but withoutair brakes, the system comprising: a first rotary fluid connectionmounted at the first end of the axle and in sealed fluid communicationwith the first pneumatic tire; a second rotary fluid connection mountedat the second end of the axle and in sealed fluid communication with thesecond pneumatic tire; a first fluid connector configured for sealedconnection to a fluid pressure source mounted to the vehicle, the firstrotary fluid connection and the second rotary fluid connection being insealed fluid communication with the first fluid connector such thatfluid flowing into the first fluid connector from the fluid pressuresource may flow substantially simultaneously into the first and secondpneumatic tires; a first one-way valve in sealed fluid communicationwith the first fluid connector and the first pneumatic tire, the firstone-way valve disposed so as to allow pressurized fluid to flow from thefirst fluid connector to the first pneumatic tire but not from the firstpneumatic tire to atmosphere when the first fluid connector is notconnected to the fluid pressure source, the first one-way valve beingfurther disposed so as to allow fluid to flow to the first pneumatictire and not from the first pneumatic tire to the second pneumatic tire;a second one-way valve in sealed fluid communication with the firstfluid connector and the second pneumatic tire, the second one-way valvedisposed so as to allow pressurized fluid to flow from the first fluidconnector to the second pneumatic tire but not from the second pneumatictire to atmosphere when the first fluid connector is not connected tothe fluid pressure source, the second one-way valve being furtherdisposed so as to allow fluid to flow to the second pneumatic tire andnot from the second pneumatic tire to the first pneumatic tire; and athird one-way valve in sealed fluid communication with the first andsecond one-way valves and the first fluid connector so as to preventpressurized fluid from flowing from the first and second one-way valvesto atmosphere.
 14. The system of claim 13, the third one-way valve insealed fluid communication with the first fluid connector, the thirdone-way valve disposed so as to prevent fluid from flowing from thefirst fluid connector to atmosphere when the first fluid connector isnot connected to the fluid pressure source.
 15. The system of claim 13,the first fluid connector comprising the third one-way valve.
 16. Thesystem of claim 13 further comprising a pressure-relief valve (PRV) insealed communication with either or both of the first and second one-wayvalves and the first fluid connector, wherein the PRV is configured torelease fluid when the fluid pressure at either or both of the first andsecond one-way valves reaches a pressure threshold.
 17. The system ofclaim 13 further comprising a second fluid connector configured forsealed connection to an external fluid pressure source external to thetrailer and the vehicle, the first rotary fluid connection and thesecond rotary fluid connection being in sealed fluid communication withthe second fluid connector such that fluid flowing into the second fluidconnector from the external fluid pressure source may flow substantiallysimultaneously into the first and second pneumatic tires.
 18. The systemof claim 17 further comprising a fourth one-way valve in sealed fluidcommunication with the second fluid connector and the first and secondpneumatic tires, the fourth one-way valve disposed so as to allowpressurized fluid to flow from the second fluid connector to the firstand second pneumatic tires but not from the first or second pneumatictires to atmosphere.
 19. The system of claim 1 further comprising asecond fluid connector configured for sealed connection to an externalfluid pressure source external to the trailer and the vehicle, the firstrotary fluid connection and the second rotary fluid connection being insealed fluid communication with the second fluid connector such thatfluid flowing into the second fluid connector from the external fluidpressure source may flow substantially simultaneously into the first andsecond pneumatic tires.
 20. The system of claim 19 further comprising asecond one-way valve in sealed fluid communication with the second fluidconnector, the second one-way valve disposed so as to prevent fluid fromflowing from the first and second pneumatic tires to atmosphere.
 21. Thesystem of claim 20, the second fluid connector comprising the secondone-way valve.
 22. The system of claim 1 further comprising ahigh-temperature warning system comprising: a normally-closed one-wayvalve configured to open upon reaching a predetermined temperature, thenormally-closed one-way valve being in sealed fluid communication withthe fluid pressure source; and a warning indicator configured toactivate when the normally-closed valve opens.
 23. The system of claim22, the high-temperature warning system further comprising a flow switchin sealed fluid communication with the normally-closed one-way valve,the flow switch configured to activate the warning indicator.
 24. Thesystem of claim 23, the warning indicator comprising a light.
 25. Thesystem of claim 22, the warning indicator comprising a sound-emittingvalve configured to emit sound when pressurized fluid flowstherethrough.
 26. The system of claim 22, the normally-closed valvecomprising a eutectic alloy configured to melt upon reaching thepredetermined temperature, the normally-closed valve being disposed in aheat-exchange relationship with the first or second end of the axle. 27.The system of claim 22, the high-temperature warning system furthercomprising a thermally-operable switch configured to activate thewarning indicator upon reaching the predetermined temperature, thethermally-operable switch being disposed in a heat-exchange relationshipwith the first or second end of the axle.
 28. The system of claim 27,the warning indicator comprising a light.